To print: Select File and then Print from your browser's menu

Title: Patients Who Switch From Tamoxifen to Anastrozole Have Longer Survival and Time to Progression: Presented at ASCO

"Patients Who Switch From Tamoxifen to Anastrozole Have Longer Survival and Time to Progression: Presented at ASCO"

By Paula Moyer ATLANTA, G.A. -- June 4, 2004 -- Patients who are switched to anastrozole after 2 years of tamoxifen therapy have a longer disease-free and overall survival, according to investigators who presented their findings here at the American Society of Clinical Oncology 2006 Annual Meeting (ASCO). "Postmenopausal women who have already started their 5-year course of tamoxifen for the treatment of hormone receptor-positive early breast cancer benefit from switching to adjuvant anastrozole, rather than continuing with tamoxifen," said principal investigator Manfred Kaufmann, MD, professor of obstetrics and gynecology, J. W. Goethe-University, of Frankfurt, Frankfurt am Main, Germany. The Anastrozole or Tamoxifen Alone or in Combination (ATAC) study previously showed that initial adjuvant treatment with anastrozole has significant efficacy and tolerability advantages over tamoxifen in postmenopausal women with hormone-sensitive early breast cancer. Dr. Kaufmann and colleagues therefore conducted the ARNO 95 study to compare outcomes in women who switched to anastrozole after 2 years of tamoxifen and those who continued their tamoxifen therapy. The women were randomized to either switch to anastrozole 1 mg/day or to continue on tamoxifen 20 or 30 mg/day for an additional 3 years after the initial 2 years of tamoxifen treatment. No adjuvant chemotherapy was given. In his presentation on June 3[^rd, Dr. Kaufmann said the researchers assessed rates of disease-free survival and overall survival, as well as the safety and tolerability associated with the switch. They analyzed data on patients' age, tumor size, and nodal status, as well as tumor grade and type of surgery.

Among the 979 women, 489 switched to anastrozole and 490 continued on tamoxifen. Follow-up was a minimum of 30.1 months.

Results showed that switching to anastrozole significantly improved disease-free survival and overall survival, with 36 recurrences reported in the switch group and 47 cases in the continuation group.

There were 15 deaths in the switched group and 28 in the continuation group, for a 47% improvement in overall survival in the anastrozole group, the investigators said.

Rates of adverse events were 22.7% and 30.8%, respectively (P =.0065). The difference was primarily due to the number of thromboembolic events in the tamoxifen group. However, 16.8% of the anastrozole group had musculoskeletal events compared with 8.0% of the continuation group.

"These results provide additional evidence that 5 years of tamoxifen is no longer the optimum adjuvant therapy for such patients," Dr. Kaufmann said.

[Presentation title: Survival Benefit of Switching to Anastrozole After 2 Years' Treatment With Tamoxifen Therapy: the ARNO 95 Study. Abstract 547]

Copyright © 2009 P\S\L Consulting Group Inc. All rights reserved. Republication or redistribution of P\S\L content is expressly prohibited without the prior written consent of P\S\L. P\S\L shall not be liable for any errors, omissions or delays in this content or any other content on its sites, newsletters or other publications, nor for any decisions or actions taken in reliance on such content.